You are not logged in. [Log In]


Forums » General Discussion » Technical Questions » Preout voltage vs amplifier input sensitivity?

Topic Options
Rate This Topic
#409577 - 01/18/15 02:03 PM Preout voltage vs amplifier input sensitivity?
Serenity_then Offline
connoisseur

Registered: 03/28/14
Posts: 1565
Loc: PEI, Canada
I have an AVR capable of max preout voltage of 6v rms. Nominal is stated as 1v rms. It will be connected to 3 external amplifier channels with an input sensitivity of 311mv for max output. They will be used for the left/center/right speakers. The AVR will handle the rest of the channels in the surround system.

Is the great difference between ouput voltage vs input sensitivity going to cause volume/trim issues between the onboard vs external powered speakers? I dont want to run the L/C/R preouts at -10 to match the onboard amplification.

Am I screwed up at how I'm thinking of this? confused
_________________________
Trevor. Cold turkey. Thanks guys. Cheers.

Top
#409579 - 01/18/15 02:27 PM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
Gr8_White_North Offline
connoisseur

Registered: 07/12/09
Posts: 2204
Loc: Whitehorse YT
I found This to be easy to understand for a simple explanation. I read the article back when I was buying my first home amp. Car amps have variable input gain so I had to study up a bit.


Edited by Socketman (01/18/15 02:28 PM)
_________________________
DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

Top
#409581 - 01/18/15 02:59 PM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
Serenity_then Offline
connoisseur

Registered: 03/28/14
Posts: 1565
Loc: PEI, Canada
Thanks for the link!

Ok, I see the formula used equates to a voltage gain of 35.49 for the external amps. Seems really high. The manual states a max dc offset of 15mv. Whatever that means.

148w into 8 ohms. 285 into 4 ohms. From .311v input. Crazy.


According to the article this setup might be on the verge of too much of a good thing. I may be approaching my AVR preamp noise floor to make the external amp work out. How does anyone elses setup compare?


Edited by Serenity_Now (01/18/15 03:03 PM)
_________________________
Trevor. Cold turkey. Thanks guys. Cheers.

Top
#409583 - 01/18/15 03:19 PM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
Gr8_White_North Offline
connoisseur

Registered: 07/12/09
Posts: 2204
Loc: Whitehorse YT
Yes that is quite high and may cause the preamp to introduce noise into the signal, especially with very sensitive speakers.
Another good read.







Edited by Socketman (01/18/15 03:21 PM)
_________________________
DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

Top
#409592 - 01/18/15 06:20 PM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
Serenity_then Offline
connoisseur

Registered: 03/28/14
Posts: 1565
Loc: PEI, Canada
Ok, I'm not so concerned now after the 2nd article. Seems the nominal 1V output is perfectly fine for the input sensitivity. I just got hung up on the 6v max figure. That must be with the trim level at +10 or so. In any case, I wont know until I try.

Thanks for the info. smile
_________________________
Trevor. Cold turkey. Thanks guys. Cheers.

Top
#409604 - 01/18/15 10:24 PM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
fredk Offline
axiomite

Registered: 12/06/07
Posts: 7786
Loc: Canada
Originally Posted By: Serenity_Now
... In any case, I wont know until I try.

Thanks for the info. smile

Hey, at least you know you don't need to turn it up to 11 to blow the roof off. smile
_________________________
Fred

-------
Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!

Top
#409617 - 01/19/15 10:26 AM Re: Preout voltage vs amplifier input sensitivity? [Re: Serenity_then]
Gr8_White_North Offline
connoisseur

Registered: 07/12/09
Posts: 2204
Loc: Whitehorse YT
Let us know how it goes. Hopefully they will maintain an equal volume level as things get turned up.
_________________________
DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

Top

Moderator:  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 
Forum Stats

15,224 Registered Members
15 Forums
23,994 Topics
424,060 Posts

Most users ever online:
883 @ 03/04/17 05:06 PM

Top Posters
Ken.C 18044
pmbuko 16437
SirQuack 13567
CV 11677
MarkSJohnson 11437
2 registered (jmone, brendo)
59 Guests and
3 Spiders online.
Key: Admin, Global Mod, Mod
Newsletter Signup